<template>
  <div id="home">
    <nav-bar class="home-nav"><div slot="center">购物街</div></nav-bar>
    <tab-control @tabClick="tabClick" ref="tabControl1"
                   :titles="['流行', '新款', '精选']"
                   class="tab-control" v-show="isTabFixed"/>
    <scroll class="content"
            ref="scroll"
            :probe-type="3"
            @scroll="contentScroll"
            :pull-up-load="true"
            @pullingUp="loadMore">
      <home-swiper :banners="banners" @swiperLoadImages="swiperLoadImages"/>
      <home-recommend-view :recommends="recommends"/>
      <home-feature-view/>
      <tab-control @tabClick="tabClick" ref="tabControl2"
                   :titles="['流行', '新款', '精选']"/>
      <goods-list :goods="showGoods"/>
    </scroll>
    <back-top @click.native="backClick" v-show="isShowBackTop"/>
  </div>
</template>

<script>
// 子组件
import HomeSwiper from './childComps/HomeSwiper'
import HomeRecommendView from './childComps/HomeRecommendView'
import HomeFeatureView from './childComps/HomeFeatureView'

// 公共组件
import NavBar from 'components/common/navbar/NavBar'
import TabControl from 'components/content/tabControl/TabControl'
import GoodsList from 'components/content/goods/GoodsList'
import Scroll from 'components/common/scroll/Scroll'
import BackTop from 'components/content/backTop/BackTop'

//axios请求数据组件
import {getHomeMutidata, getHomeGoods} from 'network/home'
import {debounce} from 'common/utils'
import {itemListenerMixin} from 'common/mixin'

export default {
  components: {
    NavBar,
    TabControl,
    GoodsList,
    Scroll,
    BackTop,

    HomeSwiper,
    HomeRecommendView,
    HomeFeatureView
  },
  data() {
    return {
      banners: [],
      recommends: [],
      goods: {
        'pop': {page: 0, list: []},
        'new': {page: 0, list: []},
        'sell': {page: 0, list: []}
      },
      currentType: 'pop',
      isShowBackTop: true,
      tabOffsetTop: 0,
      isTabFixed: false,
      saveY: 0
    }
  },
  mixins: [itemListenerMixin],
  computed: {
    showGoods() {
      return this.goods[this.currentType].list
    }
  },
  activated() {
    this.$refs.scroll.scrollTo(0, this.saveY, -100)
    this.$refs.scroll.refresh()
  },
  deactivated() {
    //1. 保存Y值
    this.saveY = this.$refs.scroll.getScrollY()

    //2. 取消全局事件的监听
    this.bus.$off('itemImageLoad', this.ItemListener)
  },
  //组件创建完就发送请求
  created() {
    //1. 请求多个数据
    this.getHomeMutidata()
    //2. 请求商品数据
    this.getHomeGoods('pop')

    this.getHomeGoods('new')

    this.getHomeGoods('sell')
  },
  mounted() {

  },
  methods: {
    /******
     *
     * 事件监听相关方法
     *
     */
    tabClick(index) {
      console.log(index);
      switch(index) {
        case 0:
          this.currentType = 'pop'
          break
        case 1:
          this.currentType = 'new'
          break
        case 2:
          this.currentType = 'sell'
          break
      }
      this.$refs.tabControl1.currentIndex = index
      this.$refs.tabControl2.currentIndex = index
    },
    backClick() {
      console.log(this.$refs.scroll);
      this.$refs.scroll.scrollTo(0, 0)
    },
    contentScroll(position) {
      //1. 判断BackTop是否显示
      this.isShowBackTop = -position.y > 1000

      //2. 决定tabControl是否吸顶
      this.isTabFixed = -position.y > this.tabOffsetTop
    },
    loadMore() {
      console.log('加载更多');
      this.getHomeGoods(this.currentType)
    },
    swiperLoadImages() {
      this.tabOffsetTop = this.$refs.tabControl2.$el.offsetTop
    },
    /**
     *
     * //网络请求相关的方法
     *
     */
    getHomeMutidata() {
      getHomeMutidata().then(res => {
        // this.result = res
        this.banners = res.data.banner.list
        this.recommends = res.data.recommend.list
      })
    },
    getHomeGoods(type) {
      const page = this.goods[type].page + 1
      getHomeGoods(type, page).then(res => {
        this.goods[type].list.push(...res.data.list)
        this.goods[type].page += 1

        //完成上拉加载更多
        this.$refs.scroll.finishPullUp()
      })
    }
  }
}
</script>

<style scoped>
  #home {
    /* margin-top: 44px; */
    height: 100vh;
  }
  .home-nav {
    background-color: var(--color-tint);
    color: white;
    /* position: fixed;
    left: 0;
    right: 0;
    top: 0;
    z-index: 9; */
  }
  .content {
    height: calc(100% - 93px);
    overflow: hidden;
    /* margin-top: 44px; */
  }
  .tab-control {
    position: relative;
    z-index: 9;
  }

  /**switch
    方法二 定位
    .content {
      position: absolute
      top: 44px
      bottom: 49px
      left: 0
      right: 0
    }
   */
</style>
